PHP Mail() Question

Hello, I hope maybe you can help me with this problem... I've been working with PHP/mySQL for about 6 months now, this is causing quite a headache! When I try to send confirmation email (from a form the user fills out) - it works fine when sending within the company network but fails when sending to other emails (like hotmail accounts). Any suggestions? I have full rights to the php.ini file on our server, I've tried editing the send_mail path, nothing seems to work! The server is running on a Solaris 5.8 machine - I'm assuming Apache server. $email, $first, $last are pulled from a submitted form (using POST). $welcome is a standard message used in several places - easier to change one file when changes are required. $toaddressSent = $email; $subjectSent = "$first $last, Your Request Has Been Received"; $contentSent = $welcome; mail($toaddressSent, $subjectSent, $contentSent, $additionalSent); Thanks! Brian _________________________________________________________________ Chat with friends online, try MSN Messenger: http://messenger.msn.com